Pilferproof package

ABSTRACT

A pilferproof plastic bag having reclosable interlocking members and a tear ribbon which forms an access opening when pulled from the bag. The tear ribbon protrudes from the side of the bag for easy finger gripping. A method of and means for making the bag by cutting and heatsealing the sides to form completely sealed side edges having the tear ribbon protruding therefrom.

United States Patent inventor Milorad Skendzic 110' West 69th St., NewYork, N.Y. 10023 Appl. No. 29,602 Filed Apr. 17, 1970 Patented Dec. 7,1971 Continuation-in-part of application Ser. No. 817,080, Apr. 17,1969. This application Apr. 17, 1970, Ser. No. 29,602

PILFERPROOF PACKAGE 3 Claims, 11 Drawing Figs.

0.8. CI 150/3, 150/66 Int. Cl 865d 17/20 Field of Search 150/3;

[56] References Cited UNITED STATES PATENTS 3,426,959 2/1969 Lemelson229/66 X 3,473,589 10/1969 Gotz 150/3 Primary E.\'aminer Donald F.Norton Attorney-Hill, Sherman, Meroni, Gross and Simpson ABSTRACT: Apilferproof plastic bag having reclosable interlocking members and atear ribbon which forms an access opening when pulled from the bag. Thetear ribbon protrudes from the side of the bag for easy finger gripping.

A method of and means for making the bag by cutting and heat-sealing thesides to form completely sealed side edges having the tear ribbonprotruding therefrom,

PILFERPROOF PACKAGE CROSS-REFERENCES TO RELATED APPLICATIONS This is acontinuation-impart of my pending application Ser. No. 817,080, filedApr. 17, I969 and entitled Pilferproof Package.

BACKGROUND OF THE INVENTION Field of the Invention In the copendingapplication identified above I have disclosed a reclosable plastic baghaving a removable tear ribbon for providing an access opening. The tearribbon is also made of plastic and is formed and extends across thefront wall of the bag. The plastic of which the tear ribbon is formedhas a greater tear strength than does the front wall of the bag so thatas it is pulled away it remains intact while the front wall of the bagimmediately adjacent the tear ribbon rips to form a narrow jagged slitor access opening into the bag.

To enable the user of the bag to easily finger-grip the tear ribbon aportion thereof is separated from the bag wall to provide a loosefinger-gripping end. In the assembled configuration or condition thereofthe bag is completely closed and sealed while one end (or perhapsdesirably both ends) of the tear ribbon protrudes away and hangs looselyfrom the face of the front wall of the bag.

While the bag disclosed in said earlier application is completelyutilitarian I have determined that improvements are desirable in severalrespects concerned primarily with the manufacture of the bag.

Thus I have ascertained that the bag of my earlier applica' tion doesnot lend itself to the most economical bag-manufacturing techniques.Generally, the techniques which have been found most economicalcontemplate the formation of long or endless sections of bagmakingmaterial, either in tubular form or else in the form of pairs ofsuperimposed plastic sheets. In either event, the construction of thebag material is uniform throughout its length and is then cut intodesired lengths and sealed along the cut edges to provide a series ofuniform bags.

The bagmaking material of my earlier application is not, however,uniform along its length, assuming the length thereof is greater thanthat required for a single bag. Thus, the tear ribbon is not formedcontinuously on the bag front wall but instead is separated therefrom atpredetermined lengths substantially equal to the length of an individualbag. This nonuniformity in bagmaking material substantially increasesmanufacturing difficulties and, concomitantly, manufacturing costs.

Among others, an object of the present invention is to provide areclosable plastic bag with a tear ribbon which is as easy andconvenient to use as that disclosed in my earlier application but whichlends itself to more economical manufacturing techniques and processes.

SUMMARY OF THE INVENTION Having in mind the above as well as otherobjects which will become apparent from the following description, theinvention may be summarized as comprising a reclosable plastic baghaving a tear ribbon formed completely from one end to the other in awall of the bag and having a finger-gripping end portion projecting fromor beyond a heat-sealed side edge of the bag. The finger-gripping end ofthe tear ribbon directly overlies a pair of cars projecting from thefront and back walls of the bag and the ears are sealed together at thedistal end of the finger-gripping end as well as immediately adjacentthe two sides thereof.

By virtue of the invention the tear ribbon, in the assembled conditionof the bag. is bonded along its entire length to the front wall of thebag, thus substantially reducing the possibility of inadvertent ruptureof the bag. Furthermore, the manufacture of the improved bag issubstantially facilitated.

Other facets of the invention involve a method of and means formanufacturing the vimproved bag. The method may be summarized ascomprising the steps of providing a longitudinal extent of bagmakingmaterial including a pair of mating plastic sheets having formed on theinside faces thereof a pair of interlocking members extending inspaced-parallel relation to the longitudinal edges of the sheets andhaving formed on one of the sheets a plastic tear ribbon extendingbetween and in spaced-parallel relation to the interlocking members andone of the longitudinal edges of the sheets, cutting the bagmakingmaterial to provide a pair of transverse side edges, at least one ofwhich includes an ear-shaped portion projecting laterally therefromsubstantially equal in width to and including a finger-gripping portionof the tear ribbon, and heat-sealing the pair of transverse side edgesand projection to form an individual bag. The corresponding means may besummarized as comprising apparatus for performing the foregoing method.

In addition to the foregoing, many other features, advantages andadditional objects of the present invention will become manifest tothose versed in the art upon making reference to the detaileddescription which follows and the accompanying sheets of drawings inwhich preferred structural embodiments incorporating the principles ofthe present invention are shown by way of illustrative example only.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an isometric view of aplastic bag or container constructed in accordance with the principlesof the present invention;

FIG. 2 is an enlarged front elevational view of a corner of the bag;

FIG. 3 is similar to FIG. 2 but shows the finger-gripping portion of atear ribbon partially dislocated from the bag;

FIG. 4 is an enlarged cross-sectional view of the upper portion of thebag taken substantially along lines IV-IV of FIG.

FIG. 4a is an enlarged cross-sectional view of the tear ribbon takenalong line lVa-IVa of FIG. 2;

FIG. 5 is a plan view of an extrusion die useful in forming bag materialand the construction of the bag shown in FIG. 1;

FIG. 6 is an enlarged fragmentary cross-sectional view taken along linesVI-VI of FIG. 5;

FIG. 7 is an isometric partial view of a cutting and sealing tool usefulin making the bag shown in FIG. 1;

FIG. 7a is an enlarged view of a portion of a tool shown in FIG. 7;

FIG. 8 is a top plan view of bag material and the tool shown in FIG. 7in the relative positions thereof as the tool cuts and seals the sideedges of individual bags; and

FIG. 9 is an enlarged vertical sectional view taken along lines IX-IX ofFIG. 8.

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS. 1-4 disclose a plasticreclosable bag or container constructed in accordance with theprinciples of the present invention. The bag is indicated generally atreference numeral 10 and comprises a front wall 11 and a rear wall 12which are interconnected along a top edge 13, a bottom edge I4 andopposite side edges 16 and 17.

The bag 10 is provided with means for selectively opening and closingthe same for repeated use and to that end may be more particularlycharacterized as comprising fastening means indicated generally atreference numeral 18 and including a pair of cooperating elongatedparallel transversely closable and releasable interlocking fasteningmembers 19 and 20 formed respectively on inner adjacent faces 21 and 22of the bag front and rear walls 11 and 12.

The interlocking members 19 and 20 are disposed in faceto-face relationin the assembled condition of the bag I0 and extend substantially theentire width of the bag in spacedparallel relation to the upper edge 13.

The specific configuration of the interlocking members I9 and 20 is thesame as that disclosed in my earlier application mentioned hereinaboveand is exemplary of many configurations known in the art with which theyshare the common characteristic of being closable as a result of theapplication of finger pressure along the length thereof and in amutually facing or transverse direction. The members 19 and 20 areopened or separated by the application thereto of opposed transverseforces along the length thereof. Such fastening members, being wellknown in the prior art, do not require a more detailed descriptionherein.

With the edges l3, 14, 16 and 17 a completely sealed interior chamber 23is formed within the bag 10. To provide an access opening into the bag atear ribbon or bead 24 is formed on the front wall 21 and extends inparallel relation to the interlocking members 19 and 20 and between saidinterlocking members and the top end or edge 13 of the bag 10.

The entire bag including the tear ribbon 24 is preferably made ofplastic and the tear ribbon 24 is joined fast to the front wall 11 sothat the two may be considered as being integral with one another. Thetear strength of the ribbon 24, however, is substantially greater thanthat of the front wall 11, or at least that portion of the front wall 11immediately adjacent to tear ribbon 24.

To that end the tear ribbon 24 may preferably be formed of athermoplastic substance having characteristics different from those ofthe thermoplastic of which the remainder of the bag 10 is made. Forexample, the thermoplastic of which the ribbon 24 is constituted canhave a greater tear strength than does the plastic of which the frontwall 11 is made and also may have a somewhat higher or substantiallyhigher extrusion temperature than that of the plastic which forms theremainder of the bag 10.

In the embodiment of the bag 10 shown in FIGS. 1-4 the tear ribbon 24extends not only across the entire width of the bag 10 but also projectsbeyond the side edges 16 and 17 thereof. The front and rear walls 11 and12 are also provided with ear-shaped portions 11a and 120 which projectfrom the side edges 17 and 16 and conform substantially in size to endportions 24b and 24a of the tear ribbon 24 which project beyond the sideedges 17 and 16.

The protruding portions 24a and 24b of the tear ribbon 24 may bedescribed as finger-gripping end portions. ln opening the bag 10 theuser grips one of the ends 240 or 24b and, holding the bag on both sidesof the gripped end, pulls the tear ribbon 24 away from the front wall11. FIGS. 1 and 3 illustrate the configuration of the tear ribbon 24after it has been partially removed from the bag 10.

The finger-gripping ends 24b and 24a are superimposed on the ear-shapedportions 110 and 12a. in the formation of the bag 10 the ends of thefront and rear walls 11 and 12 which form the side edges 16 and 17 arebonded together preferably by means of a heat seal. Upper and loweredges 26 and 27 of the ear-shaped protuberances 11a and 12a are alsoheatsealed together as is a far edge 28 thereof which coincides with thedistal end of the tear ribbon 24. Thus, as shown in the enlargedsectional view shown in FIG. 4a, the ear-shaped portions lla or 120extend just slightly above and below the tear ribbon 24 and are joinedtogether along the edges 26 and 27 thereof. In some respects, therefore,each of the fingergripping ends 24b or 24a of the tear ribbon 24 andtheir corresponding ear-shaped portions 11a and 12a of the front andrear walls 11 and 12 may be considered a unitary protuberance, and inremoving the tear strip 24 the entire multilayered protuberance isgrasped between the fingers.

As the portion 24a is pulled from the bag 10, however, the ear-shapedportion 12a of the rear wall 12 becomes severed in a manner shown atreference numeral 29 in FIG. 3. Thus, the ear-shaped portion 12a isremoved along with the fingergripping end 24a of the tear ribbon 24 aswell as with the earshaped portion 11a. The severing of the rear wallmay be achieved by a partial indentation seal placed in the rear wall 12of the protrusion 120. To achieve this result the bag material is runacross the sealing die 54 back to front, and as shown in FIG. 7a, whilethe bag is being formed by the sealing together of the bag edges by die54, section 29 of the rear wall of the ear-shaped projection 12a ispartially indented and weakened by sealing tool land segment 63a.

In order to completely open the bag 10 and to provide an access opening30 along the entire width thereof the full length of the tear ribbon 24is removed from the front wall 11. The longitudinal edges of the accessopening 30 are. of course, left in somewhat jagged condition asindicated at reference numerals 31 and 32. It is not necessary that thetear ribbon 24 be provided with finger-gripping portions 24a and 24b atboth ends thereof and the provision of two finger-gripping portions oronly one is, therefore, largely one of choice.

Referring to the tear ribbon 24, it is noted that it resides form oneend to the other largely in the general plane of the bag 10. Thefinger-gripping ends 240 and 24b thereof do not project away from thefront wall 11 and thus are not in position to be inadvertently yet quiteeasily dislocated to form an opening or rupture in the front wall 11.

Furthermore, the bag 10 is uniform in cross-sectional configurationbetween the side edges 16 and 17 and consequently a number of the bags10 can be conveniently formed from a length of bag material cut intoshorter lengths and sealed to provide at side edges 16 and 17 ofindividual bags.

A length of bagmaking material may comprise two separate superimposedplastic sheets which form the front and rear walls 11 and 12 and whichare heat-sealed along the transverse extremities thereof to provide theclosed upper and lower edges 13 and 14. The facing surfaces of theplastic sheets have the interlocking members 20 and 19 formedrespectively thereon and the tear ribbon 24 is formed on the sheetforming the front wall 11.

On the other hand, the bag material may comprise a continuous elongatedtube which is cut into appropriate lengths to form individual bags. Suchtubular material may be extruded from a die as indicated, for example,in FIGS. 5 and 6.

The die, which is indicated generally at reference numeral 33, may bemore particularly characterized as comprising a die body 34 and a dieplate 36 adjacent the die body 34. An annular groove 37, thecross-sectional width of which is related to the desired thickness ofthe walls 11 and 12, is formed in the die plate 36 and is interconnectedby means of suitable passages 38 formed in the die body 34 to a sourceof heated, pressurized, extrudable thennoplastic having predeterminedphysical characteristics.

The interlocking members 19 and 20 are formed integrally with and are ofthe same thermoplastic material as the tubular sheet which forms thefront and rear walls 11 and 12 by virtue of correspondingly shapedrecesses 39 and 40 formed in the die plate 36 and in conducting relationwith the flow passage The tear ribbon 24 may also be formedsimultaneously in the same extrusion operation in which the tubularplastic sheet and the cooperating interlocking members 19 and 20 arefonned. To that end a complementarily shaped recess 41 is formed in thedie plate 36 between recesses 39 and 40 and extends radially outwardlyof the annular groove 37, in contrast with the inwardly directedrecesses 39 and 40.

In the illustrated embodiment the recess 41 communicates with a flowpassage 42 in the die body 34 which is connected to another source ofextrudable plastic having physical characteristics different from thoseof which the plastic forming the tubular sheet and the interlockingmembers possess, at least insofar as tear strength is concerned. Thissecond thermoplastic material issues from the recess or opening 41 ontoan outer surface 43 of the tubular film forming the front wall 11 eitherbefore or after the plastic which forms the said wall has completelysolidified or become finally rigid.

As discussed in my earlier application mentioned hereinabove, theplastic issuing from the recess 41 may be heated to a temperature abovethe plasticized temperature of which the tubular film is made and as theplasticized plastic ribbon 24 is directed onto the outer surface 43 thehigher temperature of the ribbon, regardless of whether the tubular filmhas completely rigidified, will increase the temperature of the filmwhich is engaged by the ribbon to a point where the thickness thereofwill become decreased as indicated at reference numeral 44 in FIG. 4.Thus the higher the temperature to which the plastic ribbon 24 isheated, the more greatly reduced is the cross-sectional thickness ofsection 44, thereby providing a suitable degree of control over the tearforce required remove the ribbon 24 as well as the physicalcharacteristics of the jagged edges 31 and 32 of the access opening 30.

After the extrudate of the tubular film which forms the front and rearwalls 11 and 12 as well as the extrudate of the tear ribbon 24 havebecome rigidified, the ribbon 24 is fully bonded to the front wall 11and the two may therefore be considered as being integrally formed. Theribbon-forming extrudate may, of course, include a color additive toprovide ready visual notice of the tear ribbon 24.

Regardless of whether the bag material comprises a length ofcircumferentially continuous tubular film or a pair of elongated superimposed plastic sheets bonded together at the upper and lower edges, thepresent invention contemplates an improved method of making plural bagstherefrom and apparatus useful in the performance of the method.

Referring to FIGS. 8 and 9 there is disclosed somewhat schematically alength of bagmaking material indicated generally at reference numeral46. The material 46 comprises an upper and lower sheet of plastic forforming the front and rear walls of a series of bags 10 and aretherefore designated by reference numerals 11 and 12.

The bag material 46 may be transported on a conveyor or the likeindicated at 47, which conveyor may be moved by suitable means in arightward direction as the same is viewed in FIG. 8. The transverseextremities 13 and 14 of the bag material 46 are closed, either havingbeen previously heat sealed, if the front and rear walls 11 and 12 areformed of separate sheets of plastic, or otherwise comprising integralportions of the front and rear walls ll and 12 if the bag material isformed of a length of a single circumferentially continuous extrudedtubular film.

Disposed below the conveyor 47 is a stationary support member 48 andabove the conveyor 47 and the bag material 46 thereon is a bag-formingtool indicated generally at reference numeral 49.

As shown diagrammatically at reference numeral 50 (FIG. 9) the tool 49is supported for vertical movement toward and away from the backupsupport member 48, with which it is vertically aligned. The tool 49 maybe more particularly characterized as comprising a tool body 51 havingmounted on a lower wall 52 thereof a platelike member 53.

As shown in FIGS. 7 and 9, the member 53 has projecting away therefrom aknifelike land indicated generally at reference numeral 54 whichcomprises a first pair of spacedparallel longitudinal land segments 56and 57 and a second pair indicated at reference numerals 58 and 59.Situated between the land segments 56 and 59 is an H-shaped land segment60 having a pair of legs 61 and 62 extending transversely of thesegments 56 to 59 and an interconnecting leg 63 which extends inparallel relation to the segments 56 to 59.

As shown in FIG. 9 the various segments and legs which comprise the land54 are tapered to provide a narrow terminal end 64. Furthermore, theland segments are of sufficient length in a transverse cross-sectionaldirection to extend not only through both the front and rear walls 11and 12 of the bag material 46 but also to accommodate between the plate53 from which they extend and the bag material 46 a thin sheet member 66preferably having both temperature and electrical insulatingcharacteristics.

According to the principles of the present invention the conveyor 47carries the extent of bag material 46 past the backup support 48 and thetool 49. At predetermined time intervals, the duration of which dependupon the desired lengths of the individual bags 10, the conveyor 47stops and the tool 49, which theretofore is spaced from the conveyor 47and the backup support 48, is moved downwardly to the position thereofshown in FIG. 9. Meanwhile the plate 53 and the land 54 have been heatedto a temperature above the plasticizin temperature of the plastic ofwhich the bag walls l1 and l and tear ribbon 24 are formed. Heating ofthe plate 53 and the land 54 may be accomplished by connecting theretoan electrical power source as suggested by the lead wires 67 and 68shown in FIG. 9.

As the tool 49 moves downwardly the land 54 cuts through the sheets 11and 12 as well as the tear ribbon 24 sealing them transversely togetherand then cutting through them so as to provide cutouts as indicated atreference numeral 69 in FIG. 8 corresponding in shape to the shape ofthe various segments of the land 54. The tool 49 is then moved upwardlyand as the heated land 54 is withdrawn from the bag material. Thematerial of which the conveyor 47 is made should be suffi ciently heatresistant to accommodate the increased temperature of the land 54. Thesheet form insulating member 66 assists in confining the heating effectof the land segments on the plastic sheets 11 and 12 to those portionsthereof in direct contact with or immediately adjacent the varioussegments of the land 54.

The cutouts 69 are wasted material but the expense involved in thiswaste is not excessive when considered vis-a-vis the savings involved inthe manufacturing process of this invention. Furthermore, the cutoutportions can, of course, be reprocessed in the formation of bagmaterial, as will be understood by those skilled in the art.

The I-I-shaped land segment 60 is configured and arranges so as toprovide the ear-shaped portions Ila and 12a of the front and back wallsI] and I2 and to cut and heat-seal the edges of the ear-shaped portionsalong lines immediately adjacent the longitudinal edges 26 and 27 andthe distal edge 28 of the fingergripping portion 240 and 24b of the tearribbon 24. This feature, of course, enables the tear ribbon 24 to beproperly severed fromthe front wall 11 as it is gripped and pulled awayfrom the front wall 11 of the bag 10.

Although minor modifications might be suggested by those versed in theart, it should be understood that I wish to embody within the scope ofthe patent warranted hereon all such modifications as reasonably comewithin the scope of my contribution to the art.

I claim as my invention:

1. A bag comprising a pair of superimposed plastic sheets closed along atop edge, a bottom edge and a pair of side edges,

a pair of elongated interlocking members formed on the inside faces ofsaid sheets in spaced-parallel relation to said top edge, an elongatedplastic tear ribbon formed on one of said sheets and extending betweenand in parallel relation to said top edge and said interlocking members,

said tear ribbon having one end projecting beyond one of said side edgesand having a tear strength so much greater than that of the adjacentportions of said one sheet so as to form a narrow elongated accessopening when pulled therefrom, and a pair of ears integral with saidsheets projecting laterally beyond said one side edge and sealedtogether immediately adjacent the two sides and the distal end of theprojecting portion of said tear ribbon.

2. The bag is defined in claim 1 wherein said ribbon is coloreddifferent from said sheets for providing ready identification thereof.

3. The bag as defined in claim I wherein an opposite end of said teartear ribbon and another pair of ears project from the other of said sideedges to enable the tear ribbon to be finger gripped from either side ofsaid bag.

1. A bag comprising a pair of superimposed plastic sheets closed along atop edge, a bottom edge and a pair of side edges, a pair of elongatedinterlocking members formed on the inside faces of said sheets inspaced-parallel relation to said top edge, an elongated plastic tearribbon formed on one of said sheets and extending between and inparallel relation to said top edge and said interlocking members, saidtear ribbon having one end projecting beyond one of said side edges andhaving a tear strength so much greater than that of the adjacentportions of said one sheet so as to form a narrow elongated accessopening when pulled therefrom, and a pair of ears integral with saidsheets projecting laterally beyond said one side edge and sealedtogether immediately adjacent the two sides and the distal end of theprojecting portion of said tear ribbon.
 2. The bag is defined in claim 1wherein said ribbon is colored different from said sheets for providingready identification thereof.
 3. The bag as defined in claim 1 whereinan opposite end of said tear ribbon and another pair of ears projectfrom the other of said side edges to enable the tear ribbon to be fingergripped from either side of said bag.